Richard Garfield, Ph.D. is a rare Legendary Creature — Human Designer card from 30th Anniversary Misc Promos (P30M), collector number 1★. Current market price: $1.71, TCGplayer market prices via Scryfall.
You may play cards as though they were other cards of your choice with the same mana cost. You can't choose the same card twice. (Mana cost includes color.)